Abstract

Frequency modulation(FM) response of a 1.3 μm two‐electrode distributed feedback laser is studied in detail. We found that by adjusting the injection current applied to the modulated section, the FM bandwidth can be increased to a value as high as 900 MHz. However, as the bandwidth increases, the FM sensitivity decreases proportionally. This behavior is described satisfactorily by below‐threshold carrier rate equation and shown to be closely related to the injected carrier lifetime.